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arXiv · hep-th/0509151

String Pair Production in a Time-Dependent Gravitational Field

Andrew J. Tolley·Daniel H. Wesley
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Abstract

We study the pair creation of point-particles and strings in a time-dependent, weak gravitational field. We find that, for massive string states, there are surprising and significant differences between the string and point-particle results. Central to our approach is the fact that a weakly curved spacetime can be represented by a coherent state of gravitons, and therefore we employ standard techniques in string perturbation theory. String and point-particle pairs are created through tree-level interactions between the background gravitons. In particular, we focus on the production of excited string states and perform explicit calculations of the production of a set of string states of arbitrary excitation level. The differences between the string and point-particle results may contain important lessons for the pair production of strings in the strong gravitational fields of interest in cosmology and black hole physics.

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Andrew J. Tolley, Daniel H. Wesley. 2005-09-29. String Pair Production in a Time-Dependent Gravitational Field. https://doi.org/10.1103/physrevd.72.124009

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